AR is a live view of a physical scene augmented with computer-generated virtual objects such as texts, graphics, sound, etc. Currently, most AR client applications use live video images. An AR client application processes a video image digitally to add one or more virtual objects thereto. In processing the image, the AR client application matches the image content with reference images stored in the system. This process is generally referred to as image recognition. If a portion of the image is recognized to be a particular reference image, then the one or more virtual objects associated with this reference image are augmented to the image. A reference image is also known as a marker. A marker database in the AR client application is dedicated to store markers. The markers in the marker database are introduced or suggested by AR-content creators or editors. An AR-content creator usually selects a portion of the image, i.e. a sub-image of the image, and requests an AR content creation system to use the sub-image as a marker. As the marker is to be used in image recognition, it is advantageous if the suggested sub-image bears some contextual properties that enable image recognition to robustly and reliably detect this suggested sub-image in a video image under consideration and identify this sub-image unambiguously. It is desirable if the AR-content creator can determine suitability of the suggested sub-image for AR applications.
Although US2015/0161168, US2015/0161174, U.S. Pat. No. 8,645,370, US2007/0237426 and US2011/0176724 provide different ranking methods for images, these methods are not directed to AR marker creation or marker suitability ranking. US2015/0109337 provides a method for rating suitability, or “augmentability”, of an image to AR. In particular, the augmentability of the image is based on light exposure of the image, the motion of the image capturing device, features in the image, and blurriness of the image. The resultant rating output is fed back to a user for indicating augmentability of the image in AR applications. Although augmentability advice is given, how to modify the image in order to enhance augmentability is not provided. As a result, the user is required to use a trial-and-error method in finding out an image suitable for AR.
There is a need in the art to have a technique for assessing suitability of a suggested image for AR marker creation as well as providing advice on modifying the suggested image to improve the suitability. Advantageously, it is preferred that the technique provides real-time feedback to a user such that identifying suitable markers for the AR marker creation becomes efficient.